H3C XE 200 IP, Руководство по эксплуатации

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Operation Manual – Feature
H3C XE 200/2000 IP PBX
Chapter 2 Backup and Load Sharing
2-10
2.2.2 Load Sharing Mechanism
You can have the LS dynamically adjust the load capability of each PS in the same PS
group by using two parameters: relative capacity of each PS in the group, and number
of the subscriber lines accommodated by each gateway.
For example, a PS group contains two PSs: PS1 and PS2. PS1 can accommodate up
to 100 online gateways, supporting up to 200 subscriber lines as a whole. PS2 can
accommodate up to 1000 online gateways, supporting up to 2000 subscriber lines as a
whole.
Considering their actual capabilities, you can set the relative capability of PS1 to 5 and
that of PS2 to 50. When a gateway belonging to the group initiates a register request,
the LS determines which PS is to be used considering the number of subscriber lines
registered with each PS and their relative capability.
I. First registration request
When a gateway first initiates a registration request, the LS gathers information about
the load of the PS group to which the gateway belongs regardless of whether the
intended PS belongs to the same PS group.
Depending on the number of subscriber lines registered with each PS in the PS group
and their relative capabilities, the LS determines with which PS the gateway should
register. If this PS is the intended one, registration continues; if not, the system sends a
redirect message back to the gateway, indicating with which PS the gateway can
register.
II. Periodical load sharing tuning
Logoff of many gateways may break the load sharing policy that you set, resulting in
load imbalance among the PSs in a PS group. To prevent this from happening, the LS
tunes the load of each PS in the group at intervals of half an hour. When receiving
regular registration requests from gateways, the LS redirects some gateways to
register with PSs with lighter load to achieve new balance.
2.2.3 Operation of Load Sharing
To help you set the relative capability and number of permitted subscriber lines
appropriately for a PS, the following describes the actions that the system takes to
achieve load sharing:
1) Identify the existing PS groups on the LS. For example, PS groups g1, g2, and g3
are found.
2) Identify the PSs in each PS group. For example, five PSs, P1 through P5, are
found in PS group g1.